1. Technical Field Of The Invention
This invention relates generally to dough testing devices and methods. In particular, this invention relates to an apparatus and method for testing dough qualities and characteristics in a reliable and repeatable manner.
Dough testing equipment using burst testing is generally known in the mechanical arts.
2. Background Art
A particular apparatus for burst testing of doughs is, for example, the Chopin Alveographe. This device is a mechanical dough testing apparatus used for determining quality of wheats and of flours. It also tests the rheological characteristics of dough. The principle of this device is based upon bi-axial stretching of a dough sample, which under pressure expands into a large volume bubble having a very thin wall. This type of stretching emulates the deformation of the dough under the influence of gaseous pressure of biological origin, such as carbonic fermentation using yeast, or chemical origin, employing chemical yeasts.
In such an alveographe, the internal bubble pressure is recorded, that is, the air or other fluid pressure existing inside the bubble. The volume of the bubble is also measured. A particular dough, employing particular flours, can be tested according to this device, and the test results after repeated test measurements of the dough result in a close correllation between the measurements obtained and the baking results of such a dough. Therefore, this prior art device is useful in evaluating particular wheat varieties for use in dough, for evaluating particular doughs and formulations of doughs, and for testing the quality of a particular flour.
Due to inherent testing errors in the Alveograph, the measured variables for each dough sample can vary even for a highly uniform batch of dough samples. Furthermore, a large number of tests must generally be conducted in order to determine a "true" value for the dough characteristics being measured by this device, employing a statistical analysis. Such statistical analysis includes a determination of standard deviation of the measured values about some average value. Thus, the smaller the standard deviation, the greater the likelihood that the average value about which the standard deviation occurs is the true value of the variable being measured.
U.S. Pat. No. 3,160,002 to Lovette shows an automatic burst tester. This particular burst tester has graphical output as seen in FIGS. 1 and 3. An air supply as seen in FIG. 4 is used to provide the bursting pressure.
In U.S. Pat. No. 4,272,824 to Lewinger et al., a batch of ingredients is mixed in a receptacle, the mixed batch is then divided into equal portions, and weight is measured. A control device is shown for adjusting a portion of the mixed batch to be transferred, including a dividing means.
U.S. Pat. No. 2,673,463 to Kimball et al., teaches a device for determining the consistency of materials. This is particularly with reference to the mixing of dough, wherein a sample dough is made, and kneaded until an adequate consistency is reached. This patent takes note that the hygroscopic propeties of flour may vary from sack to sack, and that other controls and testing devices may be somewhat inaccurate, and that human errors also occur. A power graph is employed in this invention to aid in providing repeatable test results.
U.S. Pat. No. 2,275,341 to Braybender relates to a device for testing dough. In this device, as seen in FIG. 4, a curve is made representing the resistence to extension of the dough with respect to the extensibility of the dough. The dough is tested until it reaches a breaking point. Here, a dough sample is ruptured by an arm of a machine.
A variety of patents relating to dough testing include U.S. Pat. Nos. 1,591,360; 1,468,900; and 2,281,182. These patents are each by Chopin. Also, a French Patent to Chopin No. 733,686 relates to such testing equipment for determining properties of materials. All of these references are deemed relevant to Alveograph.